1. Field of the Invention
The present invention pertains to a three phase fluid flow measuring system including a centrifugal gas-liquid separator, a residual gas content measuring apparatus and a meter for determining the proportion of one liquid in another. The system is particularly useful for gas-water-oil mixtures being produced from underground reservoirs and the like.
2. Background
Efforts to measure the components of multi-phase fluid mixtures such as the gas-water-oil mixtures which are typically produced from oil and gas wells has resulted in the development of several types of flow measuring systems. For example, U.S. Pat. No. 4,776,210 to Lloyd A. Baillie et al and assigned to the assignee of the present invention describes a flow measuring system based on measurement of differential pressures and the measurement of the dielectric constant of the water-oil mixture separated from the gas fraction of the flowstream. Although this type of system is useful in relatively large steady state flowstreams it is not particularly attractive for use with small intermittent flowstreams such as often result from the production of fluids from individual wells.
In many oil and gas operations it is important to be able to measure the components of a multi-phase fluid flowstream produced from each well in n oil or gas well field. However, a system which is adaptable for measuring the intermittent and widely varying range of the components of a multi-phase fluid stream such as is typically produced by wells in a reservoir which is under various stimulation techniques, there is a need for a relatively low cost, simple yet effective system which is capable of measuring the volumetric flow of each component of the flowstream for various reasons including the adjustment of stimulation techniques and the allocation of net production volumes to those wells which may be owned by more than one party. It is to this end that the present invention has been developed with a view to providing an effective, compact and relatively uncomplicated flow measuring system which is particularly adapted for measuring the components of a gas-water-oil mixture of the type typically encountered in the production of underground hydrocarbon reservoirs.